Читать книгу The Circle of Knowledge: A Classified, Simplified, Visualized Book of Answers - Various - Страница 275

These animals have a wide body, which is enclosed between the arched shell of the back and the flat shell of the stomach. There are land, sea, and river tortoises. In some the head and legs can be retracted inside the shell. Over the outside of the case are horny plates which, in the hawkbill turtle are of value, as they afford the tortoise shell used for combs, etc. Turtles never have teeth, the edges of the jaws being covered with horny material. Most of the species are carnivorous. The largest species are the marine leather-backs of the tropics, which occasionally drift north to New England, and the giant species occurring on the Galapagos Islands, off the west coast of South America, and on some islands in the Indian Ocean.

Land Tortoises have a high arched shell under which the head and feet can be retracted. The feet have separate toes, and are adapted for walking. They are strictly herbivorous. Examples of this family are the large and strong Gopher-tortoises of the Carolinas, which burrow in the earth, the massive Amazon Tortoise, used for food by the natives, the Galapagos Tortoise, and the small Garden Tortoise.

Mud Tortoise (Emys lutaria) is frequently seen in Italy and the south of France. It inhabits lakes and slow-flowing waters, and feeds upon [221] small fish, spawn, frogs, water insects, etc. It lays its eggs in a hole, which it digs in the bank. Its flesh is edible. Small specimens are frequently kept in aquariums, and fed with meat, bread, lettuce leaves, etc.

Sea Turtles have flat shells between which the flipper-like feet and huge head cannot be retracted. There are no nails or separate toes, and the fore feet are much the larger. The Green Turtle (Chelone midas) is much esteemed as food, with its eggs. It lives in or near the Gulf Stream, feeds on the roots of eelgrass, comes ashore at night, during May, and lays nearly one hundred eggs, which hatch in six weeks; the laying is usually repeated several times every two weeks, near the first nest. This Turtle may attain a weight of over eight hundred pounds. The Logger-head Turtle, so-called from its huge head and neck, ranges from Brazil to Massachusetts, attains a weight half that of the Green Turtle, and feeds on fish, crustacea, conchs, etc.

The Hawk’s Bill (Eretmochelys) has pointed plates that supply the “tortoise shell” of commerce. A large specimen may yield as much as eight pounds of the “shell.” The beautiful mottled color and semi-transparent characters of this material are well known. Its manufacture is carried on in the East, a fine tortoise-shell being exported from Celebes to China.

Snapping Turtle is a large voracious turtle, common in North America along stagnant waters and along the southern Mississippi where it sometimes reaches the weight of thirty pounds. It lives on fishes, frogs, and shells, and occasionally water-fowl. It has great strength of jaw and snaps when it bites. When fattened, its flesh is often esteemed as a delicacy. It is sometimes known as the Alligator-terrapin or Alligator Turtle.

Terrapin is the popular name of many species of fresh-water and tidal-water tortoises, native to tropical and the warmer temperate countries. About twenty fresh-water species are found in the United States. But the terrapin par excellence is the Diamond-back Salt-water Terrapin, highly prized as a delicacy for the table. It is caught in salt marshes along the coast from New England to Texas, the finest being those of the Massachusetts and the northern coasts.

Crocodiles are cruel, but in one way they serve us, by eating the dead bodies of animals which float down the rivers. But for the crocodiles these bodies might poison the water. Here we see the crocodile and the little bird called the ziczac, which picks the food from between the crocodile’s teeth.